Yeah, from the title of your thread, I thought you were skootching coast-to-coast too
Anyway...so much to do in Berkeley, never enough time.
Start at the UC Berkeley campus at Bancroft Ave, work your way down Telegraph Ave. Street vendors, head shops, music stores (Rasputin, Amoeba), 510 Skateboarding is a local shop. And food of every kind (Top Dog on Durant Ave is a campus favorite).
Walk down Bancroft Ave away from campus toward downtown Berkeley. Games of Berkeley, Fantastic Comix, more food.
Drive to the "gourmet ghetto" on Shattuck Ave. for Cheeseboard pizza. Line out the door, closes at 3 pm. So good you might not notice it's vegetarian. Farmers' Market on Thursdays.
Trendy boutique outdoor shopping area on 4th Street. The Vivarium a block away sells snakes and other reptiles. Always a fun place to walk in a check out. Down the street, good cheap counter-service Indian food at Vik's.
If you have a lady to impress, go to the Berkeley Rose Garden in the Berkeley hills when the flowers are in bloom and have a picnic. Walk through the underground tunnel to Codornices Park, grab a piece of flattened cardboard, and go down the concrete slide. Further into the Berkeley Hills, check out Indian Rock if you like bouldering.